1. Field of the Invention
The present invention relates to handlers for testing a semiconductor device, and more particularly, to a handler for testing a semiconductor device, which enables testing of the semiconductor device under a desired temperature by using, not a chamber for providing a desired high, or low temperature ambient, but very simple system.
2. Background of the Related Art
In general, modular ICs, each having memory, and/or non-memory semiconductor devices connected into a circuitry system on a board, are undergone various test after production before shipment. The handler transfers the semiconductor devices, or the modular ICs (hereafter called as ‘device’) automatically in the test, wherein a picker robot carries out a process in which, when a tray, or a carrier having the devices thereon is loaded a loading stacker, a picker robot transfers the devices to be tested to a test site, inserts into a test socket, to carry out a required test, again transfers tested devices to an unloading stacker, and places the tested devices on designated trays, classifying the tested devices according to a result of the test.
In general, many of the handlers have a system which enables, not only general performance tests under a room temperature, but also a high temperature, or low temperature test, in which regular operation of the devices are tested under an extreme temperature condition of a high, or low temperature, in a range of +150° C. to −50° C. formed in an enclosed chamber by using electric heater or a liquid nitrogen spraying system.
For an example, on one side of a test site of the test handler for testing the memory semiconductor device or the modular IC, there is a preheat chamber for preheating or precooling a test tray having the semiconductor devices loaded thereon or a carrier having modular ICs loaded thereon to a preset temperature as the test tray or the carrier is moved step by step. On one side of the preheat chamber, there is a test chamber for inserting the preheated, or precooled devices in test sockets on a test board under a preset temperature, for carrying out test. On one side of the test chamber, there is a defrost chamber for restoring states of tested devices to an original room temperature, for carrying out a temperature test as the devices go through the preheat chamber, the test chamber, and the defrost chamber.
However, the forgoing related art handler provided with enclosed chambers to form a high, or low temperature ambient for carrying out the high, or low temperature test have the following problems.
First, the attachment of specially formed thick insulating material on an entire wall of the chamber for prevention of heat exchange between an inside and outside of the chamber increases a production cost of the handler as the insulating material is very expensive, and an overall size of the handler.
Second, with regard to the test tray, or the carrier in the preheat chamber or the defrost chamber that is under a temperature state for a preset time period while moving in steps, a conveyor for moving the test tray or the carrier requires very complicated mechanism, a special structure, and material for operating under extreme temperature ambient, to require difficult fabrication process and a high production cost, and difficult to maintain.
Third, the requirements for heating an entire inside space of the chamber to a desired temperature accurately for testing the devices under the accurate temperature, and maintaining the entire inside space of the chamber at a uniform temperature for setting up a thermal equilibrium between all parts inside of the chamber require, not only supply of much thermal energy, but also much time period, and has a difficulty in controlling an accurate temperature during testing.
Of course, even though there are logic handlers developed and used for testing non-memory semiconductor device, such as a logic device, having, not chamber, but a soaking plate for heating the semiconductor devices, or heating or cooling the device by direct spraying of high, or low temperature air, or the like, or transmitting heat from a heater to a surface of the device held at an index head that holds devices and inserts into a test socket, in a case many devices, such as 64 or 128 devices are loaded on a test tray and tested at a time, like the memory device, the type of heating or cooling in a chamber as above has been only one.